Yarn kind changing process for a spinning winder

Abstract

A yarn kind changing process for a spinning winder which comprises the steps of stopping winding of a bobbin being wound on a spinning spindle after a yarn kind changing instruction, cutting a sliver which extends between a draft part of a spinnig frame and a yarn supply station and joining a supply side sliver of a different kind to the sliver remaining on the draft part, starting the spindle again to wind yarn of the new kind on a layer of the yarn of the preceding kind on a winding bobbin, and removing the yarn of the new kind wound on the yarn of the preceding kind before the fully wound bobbin doffed from the spindle is subsequently supplied to a winder.

What is claimed is: 
     
       1. A yarn kind changing device operable with a spinning bobbin having first and second lengths of yarn wound thereon, said yarn kind changing device further operable with a yarn end finding device having a bobbin accepting position, bobbin processing stations, a bobbin discharging position, a rotary plate rotatable intermittently adjacent the accepting position, processing stations, and discharging position, and bypass means for returning a bobbin to the bobbin accepting position, said yarn kind changing device comprising a first yarn removing station located along the bypass means, and a yarn moving device, located adjacent said first yarn removing station, for removing said second length of yarn from the spinning bobbin. 
     
     
       2. A yarn kind changing device as claimed in claim 1, further comprising a second yarn removing station located along the bypass means, wherein said yarn removing device comprises: a sucking pipe for sucking and releasing an end of the second length of yarn, said sucking pipe having a slit extending to said second yarn removing station,   a cutter for cutting a section of yarn extending between said second yarn removing station and the slit, and   a shutter for starting and stopping a sucking action of the sucking pipe.   
     
     
       3. A yarn kind changing device as claimed in claim 2, further comprising a nozzle for injecting compressed air towards the inside of the sucking pipe. 
     
     
       4. A yarn kind changing device as claimed in claim 2, further comprising: a reading device, located between the bobbin accepting and discharging positions, for making a discrimination whether or not a bobbin having first and second lengths of yarn; and   a movable guide arranged adjacent the bobbin discharging position, said movable guide being movable to a first position to guide a bobbin to the bypass means.   
     
     
       5. A yarn kind changing device as claimed in claim 1, wherein the first length of yarn is a first kind of yarn and the second length of yarn is a second kind of yarn which is different from the first kind of yarn. 
     
     
       6. A yarn kind changing device as claimed in claim 1, wherein said yarn kind changing device is further operable with a yarn processing device and wherein the second length of yarn comprises a starter length of yarn drawn through the yarn processing device to load the yarn processing device with yarn. 
     
     
       7. A yarn changing device as claimed in claim 6, wherein the yarn processing device comprises a yarn spinning unit. 
     
     
       8. A yarn kind changing device as claimed in claim 6, wherein the first length of yarn is a first kind of yarn and the second length of yarn is a second kind of yarn which is different from the first kind of yarn. 
     
     
       9. A bobbin processing system operable on a bobbin having a first length of a first type of yarn and a second length of a second type of yarn, said system comprising: yarn removing means for removing a length of yarn from the bobbin; and   control means for controlling the yarn removing means to remove the second length of yarn from the bobbin.   
     
     
       10. A bobbin processing system as claimed in claim 9, wherein said control means comprises preset means for presetting the length of yarn which the yarn removing means removes to encompass the second length of the second type of yarn. 
     
     
       11. A bobbin processing system as claimed in claim 9, wherein said yarn removing means comprises a suction means operable for sucking yarn from the bobbin. 
     
     
       12. A bobbin processing system as claimed in claim 11, wherein said suction means comprises: a suction passage through which a suction force is communicable;   a shutter arranged to selectively traverse the suction passage and selectively obstruct communication of the suction force.   
     
     
       13. A bobbin processing system as claimed in claim 12, wherein said control means comprises shutter control means for selectively controlling the shutter to traverse the suction passage. 
     
     
       14. A bobbin processing system as claimed in claim 13, wherein said control means further comprises timing control means, having a preset time period, for controlling the selective operation of the shutter to traverse the suction passage following the lapse of said preset time period. 
     
     
       15. A bobbin processing system as claimed in claim 12, wherein: said suction passage comprises a first pipe having a first opening and a second pipe having a second opening arranged in communication with and spaced from said first opening; and   said shutter comprises a movable plate movable in the space between said first and second openings.   
     
     
       16. A bobbin processing system as claimed in claim 15, further comprising moving means operable for moving said movable plate between a first position obstructing communication between said first and second openings and a second position accommodating communication between said first and second openings. 
     
     
       17. A bobbin processing system as claimed in claim 16, wherein said control means comprises: timing means for timimg the operation of the suction means, said timing means having a preset time period;   moving control means, responsive to said timing means, for controlling the operation of said moving means to move said movable plate from said second position to said first position after the lapse of said preset time period timed by said timing means during operation of said suction means.   
     
     
       18. A bobbin processing system as claimed in claim 9, wherein said yarn removing means has a bobbin receiving position and said bobbin processing device further comprises transporting means for transporting the bobbin to and from said bobbin receiving position, said transporting means comprising: a first bobbin path having a bobbin input end, a bobbin output end and at least one bobbin processing station located between said input and output ends; and   a second bobbin path having a bobbin input end arranged adjacent said bobbin output end of said first bobbin path, said second bobbin path having a bobbin output end arranged adjacent said bobbin input end of said first bobbin path, wherein said bobbin receiving position of said yarn removing means is provided adjacent said second bobbin path between input and output ends of said second bobbin path.   
     
     
       19. A bobbin processing system as claimed in claim 18, further comprising: yarn end finding means operable for finding an end of the yarn wound about on the bobbin, said yarn end finding means located adjacent said at least one bobbin processing station;   detecting means for detecting whether the bobbin has the second length of the second type of yarn thereon; said detecting means being arranged adjacent said first bobbin path; and   transfer means, responsive to said detecting means detecting the second length of the second type of yarn, for transferring the bobbin from said output end of said first bobbin path to said input end of said second bobbin path.